KR101765850B1 - Electrophoretic display device and manufacturing method thereof - Google Patents

Abstract

A method of manufacturing an electrophoretic display device according to an embodiment of the present invention includes forming a plurality of pixel electrodes on a lower substrate and forming barrier ribs to surround the plurality of pixel electrodes; Applying a transparent substance inside the pixel region defined by the partition wall and the partition wall; Filling an electrophoretic dispersion liquid containing a plurality of charged particles and a dielectric solvent colored to display a specific color in the pixel region; Curing the transparent substance moved to the upper portion of the electrophoretic dispersion liquid by a difference in specific gravity between the transparent substance and the dielectric solvent to form a sealant layer on the partition wall and the electrophoretic dispersion liquid; And bonding the lower substrate and the upper substrate with the sealant layer interposed therebetween.

Description

ELECTROPHORETIC DISPLAY DEVICE AND MANUFACTURING METHOD THEREOF FIELD OF THE INVENTION [0001]

The present invention relates to an electrophoretic display device, and more particularly, to an electrophoretic display device capable of improving driving stability and display quality, and a method of manufacturing an electrophoretic display device capable of improving manufacturing efficiency.

An electrophoretic display device refers to an apparatus that displays an image by using an electrophoresis phenomenon in which colored charged particles move by an electric field applied from the outside. Here, the electrophoresis phenomenon means that the charged particles move in the liquid by the Coulomb force when an electric field is applied to an electrophoretic dispersion (e-ink) in which the charged particles are dispersed in the liquid.

The electrophoretic display using electrophoresis has a characteristic of bistability, so that the original image can be displayed for a long time even when the applied voltage is removed. That is, the electrophoretic display device is a display device suitable for the e-book field in which it is not required to promptly switch the screen because a constant screen can be maintained for a long time without continuously applying a voltage.

In addition, the electrophoretic display device has no dependency on the viewing angle, unlike the liquid crystal display device, and can provide a comfortable image on the eye to a degree similar to paper. In addition, Flexibility, low power consumption, and eco-like flexibility are giving rise to demand as a next generation display device.

1 is a cross-sectional view showing a structure of an electrophoretic display device according to the related art.

Referring to FIG. 1, the electrophoretic display device according to the related art includes a lower substrate 10 and an upper substrate 20 facing each other, and an electrophoretic film (not shown) interposed between the lower substrate 10 and the upper substrate 20, (30).

The lower substrate 10 includes a plurality of pixel electrodes (not shown) opposed to the common electrode 22 formed on the upper substrate 20 and a plurality of thin film transistors (not shown) which are switching elements for applying a voltage to the plurality of pixel electrodes TFT, not shown).

The electrophoretic film 30 includes a plurality of microcapsules 32 composed of charged particles and a solvent and a protective layer 34 for protecting the microcapsules 32 and adhering to the lower substrate 10 .

Here, the microcapsule 32 includes positive (+) charged particles and negative (-) charged particles and a solvent (binder) for surrounding the charged particles.

When an electric field is formed between the pixel electrode of the lower substrate 10 and the common electrode 22 of the upper substrate 20, the charged particles contained in the microcapsule 32 are moved by electrophoresis to realize an image do.

The electrophoretic display device according to the related art has a structure in which the upper substrate 20, the lower substrate 10 and the lamination electrophoretic film 30 are manufactured and then the electrophoretic film 30 is bonded to the lower substrate 10 And the upper substrate 20, as shown in Fig.

The electrophoretic film 30 is stored and transported in a state that a release film (not shown) is attached to the protective layer 34, and the release film is removed immediately before the laminating process is performed on the lower substrate 10, The protective layer 34 is attached to the lower substrate 10.

Therefore, since the lower substrate 10, the upper substrate 20, and the electrophoretic film 30 must be separately manufactured, the manufacturing process is complicated, and the manufacturing time is long, which results in a low manufacturing efficiency. In addition, since the separately prepared electrophoretic film 30 must be applied, the manufacturing cost increases.

In order to solve these problems, there has been developed a technique for internalizing the electrophoresis layer on the lower substrate. However, since the structure for internalizing the electrophoresis layer on the lower substrate and the manufacturing process technology are not matured, There is a difficulty.

An object of the present invention is to provide an electrophoretic display device having high display quality and a method of manufacturing the same.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and it is an object of the present invention to provide a manufacturing method of an electrophoretic display device which can improve manufacturing efficiency.

Disclosure of Invention Technical Problem [8] Accordingly, the present invention has been made to solve the above-mentioned problems occurring in the prior art, and it is an object of the present invention to provide an electrophoretic display device and a method of manufacturing the electrophoretic display device that can improve the driving stability and reliability of an electrophoretic dispersion built-

An object of the present invention is to provide an electrophoretic display device capable of realizing an image of high quality in various colors and a method of manufacturing the same.

An object of the present invention is to provide a method for manufacturing an electrophoretic display device that prevents the unfilled electrophoretic dispersion contained in the lower substrate and improves the filling method of the electrophoretic dispersion during the manufacturing process.

Other features and advantages of the invention will be set forth in the description which follows, or may be obvious to those skilled in the art from the description and the claims.

According to an aspect of the present invention, there is provided an electrophoretic display device including: a barrier rib formed to surround a pixel electrode formed on a lower substrate and defining a plurality of pixel regions; An electrophoretic dispersion filled in the pixel region, the electrophoretic dispersion including a plurality of charged particles colored to display a specific color and a dielectric solvent; A sealant layer formed on the barrier ribs and the electrophoretic dispersion liquid to seal the electrophoretic dispersion liquid; And an upper substrate bonded to the lower substrate with the sealant layer interposed therebetween. The sealant layer is formed of a material having a specific gravity lower than that of the dielectric solvent.

In order to achieve the above object, the sealant layer of the electrophoretic display device according to an embodiment of the present invention is formed of a transparent substance having a specific gravity of 0.1 to 0.8 [g / ml].

In order to achieve the above object, the dielectric solvent of the electrophoretic display according to the embodiment of the present invention is characterized by being a material having a specific gravity of 1.0 ± 0.2 [g / ml].

In the electrophoretic display device according to an embodiment of the present invention for achieving the above-described object, the electrophoretic dispersion liquid is internalized in the pixel region and sealed through the sealant layer.

According to another aspect of the present invention, there is provided a method of manufacturing an electrophoretic display device including forming a plurality of pixel electrodes on a lower substrate and forming barrier ribs to surround the plurality of pixel electrodes; Applying a transparent substance inside the pixel region defined by the partition wall and the partition wall; Filling an electrophoretic dispersion liquid containing a plurality of charged particles and a dielectric solvent colored to display a specific color in the pixel region; Curing the transparent substance moved to the upper portion of the electrophoretic dispersion liquid by a difference in specific gravity between the transparent substance and the dielectric solvent to form a sealant layer on the partition wall and the electrophoretic dispersion liquid; And bonding the lower substrate and the upper substrate with the sealant layer interposed therebetween.

In the method of manufacturing an electrophoretic display device according to an embodiment of the present invention, the sealant layer is formed to a thickness of 0.1 um to 40 um.

According to another aspect of the present invention, there is provided a method of manufacturing an electrophoretic display device, the method comprising filling the electrophoretic dispersion liquid in the pixel region using an inkjet printing method using at least one micro- do.

According to another aspect of the present invention, there is provided a method of manufacturing an electrophoretic display device, the method comprising: bonding the lower substrate and the upper substrate using the sealant layer as an adhesive layer.

The present invention can provide an electrophoretic display device having a high display quality and a method of manufacturing the same.

The present invention can provide an electrophoretic display device and a method of manufacturing the electrophoretic display device which can improve the driving stability and reliability of the electrophoretic dispersion internalized in the lower substrate.

The present invention can provide an electrophoretic display device and a method of manufacturing the same that can realize an image of high quality in various colors.

The present invention can provide a method of manufacturing an electrophoretic display device capable of internalizing an electrophoretic dispersion on a lower substrate.

The present invention according to the embodiments can prevent the unfilled electrophoretic dispersion that is internalized in the lower substrate and improve the filling method of the electrophoretic dispersion in the manufacturing process.

The present invention according to the embodiment can improve the manufacturing efficiency of the electrophoretic display device.

In addition, other features and advantages of the present invention may be newly understood through embodiments of the present invention.

1 is a view showing a structure of an electrophoretic display device according to the related art.
2 is a cross-sectional view illustrating an electrophoretic display device according to an embodiment of the present invention.
3 is a plan view showing a lower substrate of an electrophoretic display device according to an embodiment of the present invention.
4 is a view showing a phenomenon in which an electrophoretic dispersion and a transparent substance are separated by a specific gravity difference;
5 to 13 are views showing a manufacturing method of the electrophoretic display device according to the embodiments of the present invention.

Hereinafter, an electrophoretic display device and its manufacturing method according to embodiments of the present invention will be described in detail with reference to the accompanying drawings.

In describing an embodiment of the present invention, when it is described that a structure is formed on another structure ', on top' or 'below' and 'below', such a substrate is not limited to the case where these structures are in contact with each other, To the extent that a third structure is interposed between the first and second structures.

The present invention proposes an electrophoretic display device in which an electrophoretic dispersion containing charged particles and a solvent is embedded in a lower substrate and a method of manufacturing the same.

The technical idea of the present invention explained below is that the electrophoretic particles in the electrophoretic dispersion (electrophoretic ink) as well as the electrophoretic display device including the mono type and the color filter are red, blue, green the present invention can be similarly applied to an electrophoretic display device colored with green, yellow, cyan, magenta, black or white.

The technical idea of the present invention can be applied to all types of electrophoretic display devices whether or not mono or color is implemented, but for the convenience of explanation, a color type electrophoretic display device and its manufacturing method will be described as an example .

FIG. 2 is a cross-sectional view showing an electrophoretic display device according to an embodiment of the present invention, and FIG. 3 is a plan view showing a lower substrate of the electrophoretic display device according to an embodiment of the present invention.

2 and 3, an electrophoretic display device according to an embodiment of the present invention includes an upper substrate 200; Electrophoretic dispersion (150, 160) internalized bottom substrate (100); And a sealant layer (170).

The upper substrate 200 includes an upper base substrate 210; And a common electrode 220 formed on the upper base substrate 210.

Since the upper substrate 200 must be transparent for displaying an image, the upper base substrate 210 is formed of transparent glass or a material of a transparent plastic that is flexible.

The common electrode 220 is formed to correspond to the pixel electrode 120 of the lower substrate 100 for driving the charged particles 150 internal to the lower substrate 100 and supplies a common voltage to each pixel region. The common electrode 220 is formed by applying a conductive transparent material such as indium tin oxide (ITO) or indium zinc oxide (IZO) on the upper base substrate 210.

The lower substrate 100 includes a lower base substrate 110; A plurality of pixel electrodes 120 formed on the lower base substrate 110; A partition wall 130 formed to surround the pixel electrode 120 and defining a pixel region; And an electrophoretic layer formed in the pixel region defined by the barrier ribs (130); And a sealant layer 170 formed on the upper portion of the barrier ribs 130 and the upper portion of the pixel region (upper portion of the electrophoretic dispersion).

The electrophoretic layer is formed by filling an electrophoretic dispersion liquid in a pixel region (filling cell) defined by the barrier ribs 130, and the electrophoretic dispersion liquid is composed of a plurality of charged particles 150 and a dielectric solvent 160. Here, the dielectric solvent 160 includes a binder that improves the bistability of the charged particles.

The lower base substrate 110 may be a transparent glass substrate, a plastic substrate having flexibility, or a metal substrate. However, since the lower substrate is located on the opposite side of the screen on which the image is displayed, the lower base substrate 110 does not necessarily have to be transparent.

Although not shown in the figure, a plurality of gate lines and data lines intersecting with each other are formed on the lower base substrate 110, and a thin film transistor (TFT) is formed in a region where the plurality of gate lines and the data lines intersect with each other have.

Here, the gate line and the data line may be formed of a single film made of silver (Ag), aluminum (Al), or an alloy thereof having a low resistivity.

As another example, the gate line and the data line may be formed as a multilayer film further comprising a film made of chromium (Cr), titanium (Ti), or tantalum (Ta) excellent in electric characteristics in addition to the single film. A gate insulating film made of a nitride film (SiNx) or the like may be formed between the gate line and the data line.

A gate electrode of the thin film transistor is connected to the gate line, a source electrode thereof is connected to the data line, and a drain electrode thereof is connected to the pixel electrode 120.

The pixel electrode 120 is formed to correspond to a plurality of pixel regions defined by the barrier ribs 130, and applies a data voltage according to an input video signal according to the switching of the thin film transistor.

The pixel electrode 120 is a conductive metal layer, which is electrically connected to the drain electrode of the thin film transistor through the contact hole, and may be formed of a material such as copper, aluminum, or indium tin oxide (ITO) . Further, nickel, gold, or the like may be further laminated on the material of copper, aluminum, and indium tin oxide (ITO).

An electric field is formed in each pixel region by the data voltage applied to the common electrode 220 of the upper substrate 200 and the pixel electrode 120 of the lower substrate 100, And moves within the solvent 160 to realize an image.

The barrier ribs 130 are formed on the lower substrate to define a filling region in which the electrophoretic dispersion liquid is filled. At this time, the barrier ribs 130 are formed to have a constant height h and a width w. For example, the barrier ribs may be formed to have a height h of 10 to 100 μm and a width w of 5 to 30 μm, and are formed to surround each of the pixel electrodes 120, as shown in FIG.

Here, the barrier ribs 130 may be made of a polymer, an epoxyacrylate-based material such as a polymer, an epoxy-acrylic-based material, or the like in order to conform to the electrophoretic dispersion liquid through photolithography, mold printing, imprinting, An organic material such as a resin, or an organic material that can be coated with an organic self-assembled monolayer (SAM) layer.

The electrophoretic dispersion liquid is composed of a plurality of charged particles 150 charged with a positive (+) or negative (-) polarity and a dielectric solvent 160 including a binder.

The charged particles 150 may be at least one color of red, blue, green, yellow, cyan, magenta, black, ≪ / RTI >

The dielectric solvent 160 may be selected from the group consisting of halogenated solvents, saturated hydrocarbons, silicone oils, low molecular weight halogen-containing polymers, epoxides, Vinyl ethers, vinyl esters, aromatic hydrocarbons, toluene, naphthalene, liquid paraffinic liquids, polychlorotrifluoroethylene polymers, Materials can be used.

The electrophoretic dispersion liquid may be applied to a pixel region (filling cell) defined by the barrier ribs 130 by a die coating method, a casting method, a bar coating method, a slit coating method A dispenser method, a squeezing method, a screen printing method, an inkjet printing method, and a photolithography method. Here, the electrophoretic dispersion has a specific gravity of 1.0 ± 0.2 [g / ml].

The sealant layer 170 is formed on the barrier ribs 130 and in the upper portion of the pixel region (on top of the electrophoretic dispersion) with a thickness of 0.1 um to 40 um using a transparent substance through which light is transmitted. The sealant layer 170 seals the electrophoretic dispersion filled in the pixel region.

Since the electrophoretic dispersion liquid is sealed by the sealant layer 170, the electrophoretic dispersion filled in the pixel region is prevented from overflowing onto the barrier ribs 130 or overflowing into neighboring pixels. Then, the charged particles 150 are isolated from the common electrode 220 of the upper substrate 200.

The sealant layer 170 functions as an adhesive layer for adhering the lower substrate 100 and the upper substrate 200 to each other in the manufacturing process and to prevent the charged particles 150 from contacting the common electrode 220 It also plays a role.

The transparent material as a material of the sealant layer 170 has a specific gravity of 0.1 to 0.8 [g / ml] which is lower than the specific gravity of the electrophoretic dispersion liquid as a non-conductive material which does not generate chemical interaction with the charged particles 150 , And a density of about 1/2 of the electrophoretic dispersion.

Here, the electrophoretic dispersion liquid can be filled in the pixel region by an ink-jet printing method using a micro needle. When the electrophoretic dispersion liquid is filled in the pixel region, The bubble may be generated in the lower end region of the pixel region. In addition, bubbles may be generated in the pixel region in the process of attaching the lower substrate 100 and the upper substrate 200 together.

If bubbles are generated in the pixel region, the electrophoretic dispersion may be uncharged, which may lower the stability and reliability of the electrophoretic dispersion. Further, when a large amount of bubbles are generated in the pixel region, the electrophoretic dispersion liquid to be filled in each pixel region may overflow to the upper portion of the barrier ribs 130, or may overflow into neighboring pixel regions in severe cases.

In the case where the electrophoretic display device implements a monochrome image, the electrophoretic dispersion liquid to be filled in a specific pixel region may be filled over the neighboring pixels, but the implementation of the image may not be significant.

However, when the electrophoretic display device implements a color image, the charged particles 150 colored with a specific color are selectively filled in the pixel region so that each pixel displays a specific color. Therefore, if the electrophoretic dispersion liquid to be filled in a specific pixel region is filled over the neighboring pixel region, a serious problem that a color image can not be normally realized can occur.

The sealant layer 170 according to the exemplary embodiment of the present invention is formed on the barrier ribs 130 and the pixel region to prevent the electrophoretic dispersion liquid from overflowing onto the barrier ribs 130 and overflowing into neighboring pixel regions .

In addition, by filling the electrophoretic dispersion liquid in the pixel region using the difference in specific gravity between the transparent substance and the electrophoretic dispersion, which are the materials of the sealant layer 170, the process of filling the electrophoretic dispersion liquid, It is possible to prevent bubbles from being generated in the pixel region during the laminating process.

Specifically, the transparent sealant, which is the material of the sealant layer 170, is applied to the pixel region above the partition 130 and within the pixel region before the electrophoretic dispersion is filled. Thereafter, the electrophoretic dispersion and the transparent substance are separated due to the specific gravity difference between the materials when the electrophoretic dispersion is filled in the pixel region by ink-jet printing using a micro needle in the pixel region to which the transparent substance is applied, do.

At this time, as shown in FIG. 4, the specific gravity of the transparent substance 175 is lower than the specific gravity of the dielectric solvent 160 of the electrophoretic dispersion, and the transparent substance moves to the upper part of the electrophoretic dispersion. That is, as the electrophoretic dispersion liquid is filled from the lower portion to the upper portion of the pixel region, the transparent substance 175 moves to the upper portion of the barrier ribs 130.

When the electrophoretic dispersion liquid is filled in the pixel region, the sealant layer 170 is formed on the barrier ribs 130 and the electrophoretic dispersion liquid by irradiating the transparent substance 175 with ultraviolet rays.

The electrophoretic display device according to an embodiment of the present invention including the above-described structure includes a plurality of charged particles (hereinafter, referred to as " charged particles ") in a pixel region (filling cell) defined by the barrier ribs 130, (150) and a dielectric solvent (160). Accordingly, the electrophoretic layer is internalized in the lower substrate 100 to realize a mono image and a color image.

Further, the electrophoretic dispersion liquid can be smoothly filled in the pixel region through the sealant layer 170, and the electrophoretic dispersion liquid filled in the specific pixel region can be prevented from overflowing onto the partition wall 130, have. In addition, the driving stability and reliability of the electrophoretic dispersion can be improved, and the display quality of the electrophoretic display device can be improved.

5 to 13 are views showing a method of manufacturing an electrophoretic display device according to embodiments of the present invention. Hereinafter, a method of manufacturing an electrophoretic display device according to an embodiment of the present invention will be described with reference to FIGS. 5 to 13. FIG.

Referring to FIG. 5, a conductive layer such as copper, aluminum, or ITO is coated on a lower base substrate 110 on which a thin film transistor (TFT) is formed to correspond to each of a plurality of pixel regions.

Thereafter, the conductive layer is patterned through a photolithography process using a photoresist (photo-acryl) and an etching process to form the pixel electrodes 120 in each of the plurality of pixel regions. The pixel electrode 120 may be formed by further laminating nickel, gold, or the like on the above-described materials of copper, aluminum, and indium tin oxide (ITO).

Here, the base substrate 110 or the base film may be a transparent glass substrate, a plastic substrate having flexibility, or a metal substrate. Since the lower substrate 100 is located on the opposite side of the screen on which the image is displayed, the lower base substrate 110 does not necessarily have to be transparent.

Although not shown in FIG. 5, a gate line and a data line are formed on the lower base substrate 110, and a thin film transistor (TFT) is formed in a region where the gate line and the data line intersect.

The data line is connected to the source electrode of the thin film transistor, the gate line is connected to the gate electrode of the thin film transistor, and the drain electrode of the thin film transistor is electrically connected to the pixel electrode 120 through the contact hole. Thus, the on-off of each pixel is switched through the thin film transistor, and the data voltage applied to the data line is supplied to the pixel electrode 120. [

6, an organic material such as a polymer, an epoxy acrylic resin, an organic self-assembled monolayer (organic SAM layer) is formed on the lower base substrate 110 on which the pixel electrode 120 is formed, And then patterned to form the barrier ribs 130 so as to surround the pixel electrodes 120 formed in each of the plurality of pixel regions.

As described above, a pixel region (filled cell) in which the partition 130 is filled and the electrophoretic dispersion liquid is filled is defined. At this time, the barrier ribs 130 may be formed to have a height h of 10 um to 100 um and a width w of 5 um to 30 um.

Here, the barrier ribs 130 may be formed not only by a photolithography method, but also by imprinting, mold printing, and embossing.

Subsequently, as shown in Fig. 7, a transparent substance 175, which is a material of the sealant layer 170, is applied over the partition 130 and within the pixel region. At this time, the transparent substance 175 may be applied to have a thickness (D) of 0.1 um to 40 um.

Here, the transparent substance 175 has a specific gravity of 0.1 to 0.8 [g / ml] which is lower than the density of the electrophoretic dispersion described later and is a nonconductive material that does not generate chemical interaction with the charged particles 150, / RTI >

8, the injection equipment 180 having a plurality of micro needles 182 is aligned to correspond to the pixel region, and then the micro needle 182 is used for ink jet printing The electrophoretic dispersion liquid composed of the charged particles 150 and the dielectric solvent 160 charged with positive (+) or negative (-) polarity is filled in each of the plurality of pixel regions.

The charged particles 150 may be at least one color of red, blue, green, yellow, cyan, magenta, black, ≪ / RTI >

The dielectric solvent 160 may be selected from the group consisting of halogenated solvents, saturated hydrocarbons, silicone oils, low molecular weight halogen-containing polymers, epoxides, Vinyl ethers, vinyl esters, aromatic hydrocarbons, toluene, naphthalene, liquid paraffinic liquids, polychlorotrifluoroethylene polymers, Materials can be used.

Here, the micro needle 182 has a diameter of 0.1 um to 10 um so that the charged particles 150 and the dielectric solvent 160 can be smoothly filled in the pixel region.

When the electrophoretic display device implements the full color, the charged particles 150 can be colored in colors corresponding to the colors to be displayed by the respective cells, and colored in a specific color so that each pixel can display a specific color The charged particles 150 can be selectively filled in the pixel region.

At this time, a single micro needle 182 is formed in the injection device 180 so that the electrophoretic dispersion liquid can be sequentially filled in the entire pixel area with one micro needle 182. As another example, the same number of microneedles 182 as the entire pixel region may be formed in the injection device 180 to simultaneously fill the entire pixel region with the electrophoretic dispersion.

In the above description, the electrophoretic dispersion liquid is filled in the pixel region by the ink-jet printing method, but this is an example of the present invention. As another embodiment of the present invention, the electrophoretic dispersion can be applied not only to an inkjet printing method but also to various methods such as a die coating method, a casting method, a bar coating method, a slit coating method, a dispensing method, ) Method, a squeezing method, and a screen printing method.

9, when the electrophoretic dispersions 150 and 160 are filled in the pixel regions to which the transparent substance is applied, which is the material of the sealant layer 170, the electrophoretic dispersions 150 and 160 are formed by the specific gravity difference between the materials, And the transparent substance 170 are separated from each other.

At this time, the transparent substance 175 having a specific gravity of 0.1 to 0.8 [g / ml] has a specific gravity lower than that of the dielectric solvent 160 having a specific gravity of 1.0 ± 0.2 [g / ml] (175) moves to the top of the electrophoretic dispersion (150, 160).

As the electrophoretic dispersion liquid is filled from the lower portion to the upper portion of the pixel region, the transparent substance 175 applied to the lower portion of the original pixel region moves to the upper portion of the barrier 130. That is, when the high specific gravity water and the low specific gravity oil are filled together in the predetermined space, the transparent substance 175 floats on top of the electrophoretic dispersion liquid in the same manner as in the case where the oil rises on the water due to the specific gravity difference.

10, when the electrophoretic dispersion liquid is filled in the pixel region, ultraviolet rays are irradiated to the transparent substance 175. A sealant layer 170 is formed on the partition 130 and the electrophoretic dispersion by curing the transparent substance 175 through ultraviolet irradiation.

The sealant layer 170 also functions as an adhesive layer for bonding the lower substrate 100 and the upper substrate 200 in a manufacturing process described later. The sealant layer 170 also serves to isolate the charged particles 150 from contacting the common electrode 220.

The sealant layer 170 is formed above the barrier ribs 130 and above the pixel regions to prevent the electrophoretic dispersion liquid from overflowing onto the barrier ribs 130 and overflowing into neighboring pixel regions.

The fabrication of the lower substrate 100 is completed through the manufacturing processes of Figs. 5 to 10 described above. Meanwhile, the upper substrate 200 is manufactured by performing a manufacturing process different from the manufacturing process of forming the lower substrate 100.

Referring to FIG. 11, a common electrode 220 is formed on the upper base substrate 210 with a conductive transparent material such as indium tin oxide (ITO) or indium zinc oxide (IZO). The common electrode 220 corresponds to the pixel electrode 120 and supplies a common voltage to each pixel region for driving the charged particles 150 internal to the lower substrate 100.

Here, since the upper substrate 200 must be transparent to display an image, the upper base substrate 210 is formed of transparent glass or a transparent plastic material having flexibility.

12, the lower substrate 100 and the upper substrate 200 are bonded together using a sealant layer 170 formed on the lower substrate 100 as an adhesive layer. At this time, the upper substrate 200 and the lower substrate 100 may be joined together by a pressurizing process to apply a predetermined pressure, and an annealing process may be performed together with the pressurizing process.

The method of manufacturing an electrophoretic display device according to an embodiment of the present invention includes the steps of forming a sealant layer 170 on an electrophoretic dispersion using a specific gravity difference between a transparent substance 175 as a material of the sealant layer 170 and an electrophoretic dispersion liquid, It is possible to prevent bubbles from being generated in the pixel region during the process of filling the electrophoretic dispersion liquid and the process of attaching the lower substrate 100 and the upper substrate 200 together. Accordingly, the driving stability and reliability of the electrophoretic dispersion internalized in the lower substrate 100 can be improved, and the manufacturing efficiency of the electrophoretic display device can be improved.

In another embodiment of the present invention, the upper substrate 200 is disposed on the lower substrate 100 after filling the pixel region with the electrophoretic dispersion liquid. The sealant layer 170 may be formed on the partition 130 and on the electrophoretic dispersion by irradiating ultraviolet (UV) light to the transparent sealant 175 to cure the transparent sealant 175. At this time, the lower substrate 100 and the upper substrate 200 are bonded together using the sealant layer 170 as an adhesive layer.

Although not shown in the drawings, the lower substrate 100 and the upper substrate 200 may be bonded together by forming a substance in the outer portion of the display region of the upper substrate 200. [

The manufacturing method of the electrophoretic display device according to the embodiments of the present invention has an advantage of being able to apply the manufacturing infra used in the manufacturing process of the conventional liquid crystal display device.

It will be understood by those skilled in the art that the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof.

It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. The scope of the present invention is defined by the appended claims rather than the detailed description and all changes or modifications derived from the meaning and scope of the claims and their equivalents are to be construed as being included within the scope of the present invention do.

100: lower substrate 110: lower base substrate
120: pixel electrode 130: barrier rib
150: charged particle 160: dielectric solvent
170: sealant layer 175: transparent substance
180: Infusion equipment 182: Micro needle
200: upper substrate 210: upper base substrate
220: common electrode

Claims (15)

delete delete delete delete delete delete delete delete Forming a plurality of pixel electrodes on a lower substrate and forming barrier ribs to surround the plurality of pixel electrodes;
Applying a transparent substance inside the pixel region defined by the partition wall and the partition wall;
Filling an electrophoretic dispersion containing a plurality of charged particles and a dielectric solvent colored to display a specific color inside the pixel region to which the transparent substance is applied using an injection apparatus having at least one micro needle formed therein;
Curing the transparent substance moved to the upper portion of the electrophoretic dispersion liquid by the difference in specific gravity between the transparent substance and the dielectric solvent to form a sealant layer on the partition wall and the electrophoretic dispersion liquid; And
And adhering the lower substrate and the upper substrate with the sealant layer interposed therebetween. 10. The method of claim 9,
Wherein the dielectric solvent is a substance having a specific gravity of 1.0 ± 0.2 [g / ml], and the transparent substance is a non-conductive substance having a specific gravity of 0.1 to 0.8 [g / ml] . The method of claim 9, wherein the sealant layer
Wherein the first electrode is formed of a non-conductive material and the first electrode is formed to a thickness of 0.1 mu m to 40 mu m. 10. The method of claim 9,
Wherein the electrophoretic dispersion liquid is filled in the pixel region by an inkjet printing method or a dispensing method. 10. The method of claim 9, wherein the microneedles
Wherein the electrophoretic display device has a diameter of 0.1 um to 10 um. 10. The method of claim 9,
The sealant layer
Separating the electrophoretic dispersion from a common electrode formed on the upper substrate,
Wherein the electrophoretic dispersion liquid comprises:
Wherein the sealant layer is internalized in the pixel region and sealed through the sealant layer. 10. The method of claim 9,
Wherein the lower substrate and the upper substrate are bonded together using the sealant layer as an adhesive layer.

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